<!DOCTYPE html>
<html>

<head>

    <style>
    
        div {
            display: block;
            width: 50%;
            margin: 10px auto;
            }
        .mydiv {
            width: 200px;
            height: 200px;
            background-color: aqua;
        }
        .mydiv:hover {
            width: 100%;
            height: 100vh;
            background-color: rgb(7, 36, 36);
        }
        /* ul >li {
  border: 5px solid red;
} */
    </style>
</head>

<body>

    <div class="mydiv"></div>

    <ul>
        <li>Unordered item</li>
        <li>Unordered item
          <ol>
            <li>Item 1</li>
            <li>Item 2</li>
          </ol>
        </li>
        <li>Unordered item</li>
        <li>Unordered item</li>
        <li>Unordered item</li>
      </ul>

</body>

</html>